During many attempts to convert NTSC to PAL and vice versa, I repeatedly encountered jitter, movement fluidity loss, and increasing picture to audio sync loss.
I only refer to either full-frame DV and MPEG2 (DVD-type) formats.
I applied many techniques from de-interlacing to extrapolate fps to overcome the odd 29.97 fps to 25 fps conversion to repair jitter and movement fluidity loss, and strip-off the audio from the original and re-weave it in the target to repair picture to audio sync loss.
The curious thing is that sometimes it works and sometimes it doesn't as if to hint that there is no consistent original structure.
Some editors (e.g Vegas) and converters (e.g MainConcept) may provide a sort of "one-stop" solution, but the result is usually poor in this aspect, and to make the best of what's there I usually have to go through 3 to 5 station render, to complete it.
I was recently told Canopus Procoder may do the job properly, and thought of buying one. Can anyone confirm? Any other suggestions?